Segmented horizontal ring and cooperative drive assembly

ABSTRACT

A segmented pull ring designed for an apparatus for particle transfer from a storage pile of the type utilizing a rotatable pull ring mounted about an upright axis of rotation within the pile and having sweep means for engagement against the pile. The segmented pull ring accommodates minor construction variances encountered in large diameter circular guides for the ring. It also makes possible the utilization of conventional roller chain members to provide a constant pitch drive mechanism for rotation of the ring by meshing engagement with a movable powered sprocket.

United States Patent Appl. No. Filed Patented Assignee SEGMENTED HORIZONTAL RING AND COOPERATIVE DRIVE ASSEMBLY 8 Claims, 8 Drawing Figs.

U.S. Cl 214/10,

198/137,198/170,198/171,198/212,214/17 D Int. Cl 865g 65/42 Field of Search 214/17.8,

[56] References Cited UNITED STATES PATENTS 2,538,144 1/1951 Carretto 198/137 3,011,658 12/1961 Peterson... 214/17.82 UX 3,394,825 7/1968 Reed 214/17.82

Primary Examiner-Robert G. Sheridan Att0rney-Wells & St. John z DB0 Di 0 o 2 j 4 fie /5 ,5 4 I/ 2.;! 0 I6 A o O///3 )4 l Q I27 22 I #16 l ii I 0 25 l I 1 [I l i I! l I l ll I 1 ll l 17 I ll l 0 ll 1 5 PATENTED on s IBTI SHEU 2 [If 5 PATENTEU um 51971 SHEET 3 [1F 5 SEGMENTED HORIZONTAL RING AND COOPERATIVE DRIVE ASSEMBLY BACKGROUND OF THE INVENTION Peterson. In this type of apparatus, a storage pile of particulated material such as sawdust is placed on a support, such as a horizontal surface. The pile is encircled by a rotatable pull ring having one or more sweeps pulled by the ring and movably directed toward the pile. As the ring is rotated, the sweeps drag radially inward across the supporting surface and work against the edge of the pile, causing material from the pile to be moved across recessed conveyors that extend beneath the pile supporting surface.

In adapting the basic design of the apparatus shown in the Peterson patent to large diameter installations across the circular ring, difficulty has been encountered in fabrication procedures for the circular ring. The pull ring and itscomplementing circular guides, which must be finally fabricated at the site, are often slightly misaligned. Extreme difficulty is involved in insuring the true circular character of the various elements for guiding the ring, as well as the ring structure itself.

Difficulties also have been encountered in rotating large diameter rings. Prior to the instant discovery, it has been necessary to rotate the ring by wrapping a chain about its exterior diameter, relying upon frictional engagement of the chain against the ring for the transmission of rotational force. This was due to the difficulty involved in producing a constant pitch gear about the ring and insuring proper meshing contact of the gear with a stationary drive unit adjacent to the ring.

To resolve these problems, the present invention provides a segmented pull ring made up of a number of arcuate sections pivotally joined to one another. It is guided by a fixed cylindrical structure that is stationary and carried by the support. The pivotal connections of the pulling ring are provided by an encircling roller chain fixed to the ring segments which also serves as a constant pitch gear member mounted about the entire ring periphery. The pivotal movement provided is capable of accommodating slight variations in the cylindrical guide structure. Easily manipulated adjustment means is also provided for accommodating the individual ring segments to the cylindrical guide members during installation.

SUMMARY OF THE INVENTION The invention comprises an improvement in a pull ring structure movably mounted about an upright axis of rotation within a particle pile and having means attached to the ring for dragging engagement against the pile responsive to such ring movement. The improvement essentially comprises the use of a number of arcuate ring segments, means joining adjacent pairs of the segments in end to end positions in a continuous endless string and generally cylindrical guide means engaged by the segments to maintain the string of segments in a substantially circular path that has as its center the desired axis of rotation. Novel drive means are also provided for moving the segments in unison about their desired circular path. Means is also provided on each segment for permitting selective radial adjustment of the segment with respect to the axis of rotation of the ring.

It is one object of this invention to provide a segmented ring structure which facilitates both production of the apparatus for particle transfer and subsequent field installation of the equipment.

Another object of the invention is to provide an improved rotatable ring structure that is more capable of adapting to guiding cylindrical surfaces fabricated in the field.

Another object of this invention is to provide an improved drive mechanism for rotating the pull ring, including equally spaced roller elements mounted about the periphery of the ring and capable of being drivingly engaged by a powered sprocket assembly.

These and further objects will be evident from the following description and the accompanying drawings, which relate to a preferred form of the invention. It is to be understood that this form of the invention is presented by way of example only and that modifications and changes can be made in the precise nature of the structure without deviating from the essentials described.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a portion of the particle transfer ap paratus illustrating ring assembly and a single sweep in relation to the structure previously developed;

FIG. 2 is an enlarged cross sectional view through a ring segment as seen along line 2--2 in FIG. 1;

FIG. 3 is a side elevation view of a portion of the ring segment as seen along line 3-3 in FIG. 1;

FIG. 4 is an enlarged fragmentary top view showing the joinder between two adjacent ring segments;

FIG. 5 is an enlarged sectional view taken along line 5-5 in FIG. 3;

FIG. 6 is a fragmentary top view showing the drive assembly for the ring;

FIG. 7 is an elevation view taken along line 7-7 in FIG. 6; and

FIG. 8 is a sectional view taken along line 88 in FIG. 6.

THE PREFERRED EMBODIMENT The structure described herein is an improvement in one of the components shown in U.S. Pat. No. 3,0l 1,658 to John L. Peterson. Reference is made to the specification of this prior patent for greater detail as to the various components discussed herein.

Referring to FIG. I which isa plan view of a portion of the apparatus, the unit essentially comprises a support or floor I0 which typically constitutes a concrete slab. The support 10 normally includes an upper horizontal surface on which a pile of sawdust or other bulk particulate material is stored. This pile is designated in FIG. I by the numeral 11.

Mounted about the pile 11 on the support 10 is a rotatable pull ring assembly 12. The pull ring assembly 12 is elevationally guided by wheel assemblies 23 which bear on the support 10 and by a fixed guide ring assembly 13 that is stationary with respect to the support 10. The rotatable pull ring assembly 12 has a plurality of movable sweep assemblies 14 extending inwardly from it. Each sweep assembly 14 is movably connected to the ring assembly 12 at its outer end. The inner end of each sweep assembly 14 is dragged along support 10 and against the periphery of pile 11 in response to rotation of pull ring assembly 12 in the direction of rotation shown by the arrow 15. In the accompanying drawing, the sweep assembly 14 is shown as comprising a plurality of pivotally connected buckets which drag across the surface of the support 10 and move inwardly from the pull ring assembly 12 due to the frictional forces exerted thereon. This disclosure is not intended to be limited to this particular type of sweep assembly. The sweep assembly 14 might constitute a rigid arm, might be constructed partially or completely of flexible materials, and might be moved inwardly by either frictional forces or by positive powered devices such as hydraulic cylinders.

The rotating pull ring assembly 12 and the fixed guide ring assembly 13 are housed beneath a protective stationary escape ring. The escape ring 16 defines a protected area within which the sweep assemblies 14 can retract when the periphery of pile 11 reaches the area adjacent to pull ring assembly 12. The sweep assembly 14 therefore does not have to work beneath pile II and is at all times free to work against the periphery of the pile while under the escape ring 16.

As the pull ring assembly I2 constantly rotates in the direction shown by arrow 15, the sweep assemblies 14 are constantly urged inward and engage the edges of the pile II. The material freed from the pile is then dragged across grates 17 that are flush with the surface of the support 10. Recessed beneath the grates 17 are conveying devices for carrying the material away from the area.

The details of the segmented ring assembly 12 are shown in FIGS. 1 through 5. The details of the drive unit that rotates the ring assembly 12 are shown in FlGS. 6-8.

The pull ring assembly 12 can be manufactured in any desired size, dependent upon the diameter of the pile 11 which is to be surrounded thereby. installations of this equipment have encompassed working diameters of 12 feet to 125 feet or larger. When constructing such an installation, considerable difficulty is encountered because of the limitations of fabrication techniques for welding or otherwise joining the portions of the ring and guiding assemblies in the field it was difficult to construct a perfectly cylindrical guide ring of a chosen circumference.

One solution to these difficulties has been to provide adjustment of the pull ring diameter to match the diameter of the guide ring assembly. This does not lend itself to an apparatus wherein a driven gear structure is fixed about the pull ring, since it necessarily would vary the gear diameter and require pitch adjustment.

The solution provided herein is to use a pull ring of a chosen fixed circumference and to provide means to adjust the support rollers on the pull ring to match the physical limitations of the guide ring assembly.

The use of a segmented ring assembly 12 permits the segments of the ring assembly 12 to accommodate variations from a perfect cylinder along the periphery of the fixed guide ring assembly 13. The individual segments of the ring assembly 12 are functionally identical, although they might vary in length to meet the size requirements of a particular installation. Only a single segment will be discussed herein. Each of the segments shown by way of example essentially comprises an arcuate outer channel 20 and an inner channel 21 that forms a chord across the arcuate configuration of channel 20. The two channels 20, 21 are rigidly joined to one another by longitudinally spaced plates 22 welded or otherwise secured to them across their upper and lower surfaces.

Each segment 18 is elevationally supported at each end by vertical wheel assembly 23. The forward end of each segment 18 is radially guided by a thrust wheel assembly 24 including upper and lower wheels 25 which respectively engage upper and lower circular rings 26 beneath the escape ring 16 (FIG. 2).

Extending about the entire pull ring assembly 12 is an endless length of roller chain 27. It includes supporting plates 28 welded to the outer surfaces of channel 20 along the length of each segment 18, and pivoted plates 30 which rotatably support upright rollers 31. The rollers 31 are equally spaced from one another all about the periphery of the ring assembly 12. There is one modification in the chain assembly, best seen at FIGS. 4 and 5. At the trailing end of each segment 18, the final plate 30 that projects rearwardly from the segment is welded to the supporting plate 28 at both the top and bottom of the chain 27. These particular plates are indicated by the reference numeral 30a. The pivotal connection between the plates 30a and the plate 28 in the following segment is indicated at 31a. The axis of the roller 31a constitutes the pivotal axis between the adjacent pair of segments 18. This axis at 31a is normally vertical and is parallel to the axis of rotation of the pull ring assembly 12, which is normally located at the center of the particle pile 11.

Installation of the pull ring assembly 12 follows fabrication of the guiding rings 26. Rings 26 are constructed at the site with as much accuracy as possible in order that the outer surfaces of the rings 26 will present a substantially cylindrical configuration having a central axis coincident with the desired axis of rotation of the ring assembly 12. However, because of fabrication limitations, particularly during this type of field installation, there will normally be variations in the surfaces presented by rings 26 to the thrust wheel assemblies 24.

The thrust wheel assemblies 24 are mounted on the channels 21 in such fashion as to permit radial adjustment in the forward end of each segment 18 with respect to the axis of rotation at the center of the unit. This is accomplished by the mounting of each thrust wheel assembly 24 on a plate 32 slidably mounted along a longitudinal aperture 33 provided along the web of the channel 21. A block 34 protrudes through aperture 33 and is threadably engaged by an elongated bolt 35. The bolt 35 is rotatably journaled by an end plate 36 at the forward end of the segment 18 and by a parallel intermediate plate 37 that extends between the channels 20 and 21 (FIG. 5). Each bolt 35 can be rotated to move the thrust wheel assembly 24 forward or rearward along the channel 21 and thereby move the adjacent end of the segment 18 toward or away from the axis of rotation of the pull ring assembly 12. If the thrust wheel assemblies 24 on each segment 18 are initially positioned in identical locations with respect to the supporting segments 18, each can be adjusted an identical amount until a substantially constant spacing is achieved between the pull ring and guiding rings about the entire unit. Plate 32 is then welded to channel 21.

The pivotal connection that exists along the chain 27 between each pair of adjacent segments 18 permits the individual segments 18 to move inwardly and outwardly with respect to the ring axis of rotation while maintaining this preset spacing. The segmented pull ring assembly 12 therefore follows the contour of ring assembly 13 and adapts to minor variations in the fixed ring assembly 13 during the continuous rotational movement necessary for operation of the apparatus.

As seen in FIGS. 1 and 2, the segments 18 that pull the sweep assemblies 14 each include an inwardly directed horizontal bracket 40 that protrudes between the upper and lower rings 26. The outer end of each sweep assembly 14 is pivoted to one of the brackets 40 and is thereby pulled about the periphery ofthe support 10.

The drive apparatus for rotating the ring assembly 12 is illustrated in FIGS. 6 through 8. lt is mounted on the supporting foundation for the particle transfer apparatus immediately adjacent to the ring assembly 12. 1t normally would be enclosed in a protective housing which is not illustrated herein.

The drive unit includes a motor 41 and connected transmission units 42. The output sprocket 43 of the transmission unit 42 is drivingly connected to a transfer sprocket 44 and a sprocket 47 on a common hub rotatably mounted on a shaft 45. Shaft 45 is journaled by upper and lower fixed bearings. The driving connection is accomplished through chain 46. Sprocket 47 drives a sprocket 48 that is rotatably supported on a shaft 50 at the outer end of a pivot arm 51. The pivot arm 51 is fixed to shaft 45 for pivotal movement about the common axis of sprockets 44 and 47. The driving connection between sprockets 47 and 48 is illustrated as being a length of chain 52.

The final drive sprocket S3 fixed to shaft 50 is preferably of the type that tangentially engages the rollers 31 of chain 27 so as to eliminate the separating forces otherwise encountered during disengagement of the chain.

The intended direction of rotation of the ring assembly 12 is illustrated in FIG. 6 by the arrow 54. To accomplish this, the sprocket 53 is rotated in the direction shown by arrow 55. The normal forces exerted on the teeth of sprocket 53 tend to cause the sprocket 53 to move toward ring assembly 12 by pivoting the arm 51 in a clockwise direction as seen in FIG. 6. The sprocket teeth of sprocket 53 act as guides for the sprocket, as they bear against the outer arcuate surfaces of channels 20. This light bearing pressure insures proper meshing relation between the pitch diameter of sprocket 53 and the instantaneous effective pitch diameter of pull ring assembly 12 at its point of contact with sprocket 53. Arm 51 is lightly biased toward the ring assembly 12 by a compression spring 56 mounted on a pivoted support shaft 57. The force of spring 56 maintains sprockets 53 in correct driving engagement with the chain unit 27 when the unit is at rest.

The pivotal mounting of arm 51 and sprocket 53 normally serves to maintain proper sprocket to chain relation despite the possible variations in the position of the chain rollers 31 due to the segmented nature of the pull ring assembly 12 as discussed above. The sprocket 53 is fully capable of being adapted to the configuration of the ring segments 18 with respect to the axis of rotation of pull ring assembly 12, and has been found to insure proper rotation of pull ring assembly 12 under normal operational circumstances, regardless of deviations from a perfectly circular configuration and regardless of operating variations in the load imposed upon the ring assembly 12 by varying pile volumes and shapes.

The above structure greatly facilitate installation of the particle handling apparatus by permitting factory fabrication of the segments 18 and other operating elements and better accommodating field application procedures in the installation of large diameter structures. The apparatus can be used about an open pile or in a suitable enclosure. The roller chain 27 readily provides a fixed pitch gear about the rotatably ring assembly 12, permitting replacement of any individual segment 18 when such a replacement becomes necessary. The advantages in permitting adjustment of the ring assembly 12 with respect to variations that normally occur in the fixed guide ring assembly 13 have been discussed above. In addition, this apparatus permits large diameter rings to be driven directly by the described drive unit, eliminating the inherent difficulties encountered by a frictional drive assembly designed to withstand heavy load factors in a large operating installation.

Many variations might be made in the specific structure discussed without deviating from the general concepts of this disclosure. Such changes, such as differing mounting arrangements for the segment support rollers and variations in the drive unit as dictated by particular component parts, are believed to be within the skill of one within this art and encompassed within the scope of this disclosure.

Having thus described our invention, we claim:

1. In an apparatus for particle transfer from a storage pile of the type utilizing a pull ring movably mounted about an upright axis of rotation within the pile and having means attached to the pull ring for dragging engagement against the pile responsive to such pull ring movement;

an improvement in the pull ring structure comprising;

a pull ring having a preselected fixed diameter;

stationary guide means including a cylindrical surface centered about said upright axis;

and radially adjustable roller means mounted to said pull ring in engagement with the cylindrical surface of said stationary guide means.

2. An apparatus as set out in claim 1 wherein said pull ring comprises:

a plurality of arcuate segments mounted end to end in a continuous endless string, the adjacent ends of the respective segments being pivotally connected to one another about axes parallel to said upright axis.

3. The apparatus as set out in claim 2 wherein the segments are joined by an endless roller,chain fixed thereto in a substantially circular path centered about said upright axis.

4. The apparatus as set out in claim 3 wherein the adjacent segments are each joined along the roller chain by a first chain element fixed to the remaining segment, said first and second chain elements being joined to one another about a pivot axis parallel to said upright axis.

5. The apparatus asset out in claim 1 further comprising:

drive means operatively connected to said pull ring for rotating the pull ring about said upright axis.

6. The apparatus as set out in claim 1 wherein said pull ring comprises:

a plurality of arcuate segments arranged end to end in a substantially circular path centered about said upright axis; an endless length of roller chain encircling said segments and having the side plates thereof fixed to the respective segments in a circular configuration of fixed diameter centered about the upright axis, the roller elements of said chain being aligned parallel to said upright axis; and drive means operatively engaged with the chain for selectively rotating the chain and segments about said upright axis.

7. The apparatus as set out in claim 6 wherein said drill means comprises:

a sprocket in meshing engagement with the chain;

a support arm rotatably supporting said sprocket about an axis parallel to said upright axis;

said support arm being pivotally mounted about a stationary axis spaced from and parallel to said sprocket axis to permit limited radial movement of the sprocket axis relative to said upright axis;

and powered means operatively connected to said sprocket to selectively rotate the sprocket about its axis on said support arm.

8. In an apparatus for particle transfer from a storage pile of the type utilizing a pull ring movably mounted about an upright axis of rotation within the pile and having means attached to the pull ring for dragging engagement against the pile responsive to such pull ring movement;

a plurality of pull ring segments, each including an outer arcuate member and an inner chord member;

an endless length of roller chain extending about and fixed to the arcuate members of said segments;

a stationary guide ring including a continuous cylindrical surface centered about said axis of rotation;

and rollers mounted to the segments about axes respectively parallel to said axis of rotation, said rollers being in peripheral rolling engagement with said guide ring and being radially adjustable relative to said upright axis. 

1. In an apparatus for particle transfer from a storage pile of the type utilizing a pull ring movably mounted about an upright axis of rotation within the pile and having means attached to the pull ring for dragging engagement against the pile responsive to such pull ring movement; an improvement in the pull ring structure comprising; a pull ring having a preselected fixed diameter; statioNary guide means including a cylindrical surface centered about said upright axis; and radially adjustable roller means mounted to said pull ring in engagement with the cylindrical surface of said stationary guide means.
 2. An apparatus as set out in claim 1 wherein said pull ring comprises: a plurality of arcuate segments mounted end to end in a continuous endless string, the adjacent ends of the respective segments being pivotally connected to one another about axes parallel to said upright axis.
 3. The apparatus as set out in claim 2 wherein the segments are joined by an endless roller chain fixed thereto in a substantially circular path centered about said upright axis.
 4. The apparatus as set out in claim 3 wherein the adjacent segments are each joined along the roller chain by a first chain element fixed to the remaining segment, said first and second chain elements being joined to one another about a pivot axis parallel to said upright axis.
 5. The apparatus as set out in claim 1 further comprising: drive means operatively connected to said pull ring for rotating the pull ring about said upright axis.
 6. The apparatus as set out in claim 1 wherein said pull ring comprises: a plurality of arcuate segments arranged end to end in a substantially circular path centered about said upright axis; an endless length of roller chain encircling said segments and having the side plates thereof fixed to the respective segments in a circular configuration of fixed diameter centered about the upright axis, the roller elements of said chain being aligned parallel to said upright axis; and drive means operatively engaged with the chain for selectively rotating the chain and segments about said upright axis.
 7. The apparatus as set out in claim 6 wherein said drill means comprises: a sprocket in meshing engagement with the chain; a support arm rotatably supporting said sprocket about an axis parallel to said upright axis; said support arm being pivotally mounted about a stationary axis spaced from and parallel to said sprocket axis to permit limited radial movement of the sprocket axis relative to said upright axis; and powered means operatively connected to said sprocket to selectively rotate the sprocket about its axis on said support arm.
 8. In an apparatus for particle transfer from a storage pile of the type utilizing a pull ring movably mounted about an upright axis of rotation within the pile and having means attached to the pull ring for dragging engagement against the pile responsive to such pull ring movement; a plurality of pull ring segments, each including an outer arcuate member and an inner chord member; an endless length of roller chain extending about and fixed to the arcuate members of said segments; a stationary guide ring including a continuous cylindrical surface centered about said axis of rotation; and rollers mounted to the segments about axes respectively parallel to said axis of rotation, said rollers being in peripheral rolling engagement with said guide ring and being radially adjustable relative to said upright axis. 